Risk of further decline in renal function after the use of oral sodium phosphate or polyethylene glycol in patients with a preexisting glomerular filtration rate below 60 ml/min.
OBJECTIVE
The aim of this study was to estimate the risk of further creatinine increase in patients with preexisting renal disease after the use of oral sodium phosphate (OSP) versus polyethylene glycol (PEG), and to study usage patterns of OSP in relation to renal function.


METHODS
A cohort study was done using clinical records and electronic patient information from the Henry Ford Health System (HFHS) in patients who had used either OSP or PEG for colonoscopy between February 1999 and April 2006. Among patients with an estimated GFR < 60 ml/min before colonoscopy, we identified cases with an unexplained creatinine increase of > or = 0.5 mg/dl within 14 days after colonoscopy.


RESULTS
We identified 7,971 OSP and 1,511 PEG users. Relative use of OSP versus PEG decreased from 88.0% before 2004 to 48.4% in 2006. 70.2% of OSP users had no recorded creatinine determination within 60 days before colonoscopy, and this proportion did not decrease over time. The study population included 317 patients with a baseline GFR < 60 ml/min, and we identified one case with an unexplained creatinine increase > or = 0.5 mg/dl among 191 PEG users (0.5%) versus eight cases among 126 OSP users (6.3%). Unadjusted and adjusted relative risk estimates on comparing OSP with PEG were 12.1 (95% CI, 1.5-95.8) and 12.6 (95% CI, 1.5-106.5), respectively.


CONCLUSIONS
In patients with preexisting renal disease, OSP use was associated with an increased risk of aggravated renal dysfunction versus PEG. Creatinine measurement with GFR estimation should be done before OSP administration in order to avoid its use in patients with renal disease.
Russmann
Stefan
S
The Degge Group, Arlington, Virginia 22209, USA.
Lamerato
Lois
L
Motsko
Stephen P
SP
Pezzullo
John C
JC
Faber
Mark D
MD
Jones
Judith K
JK
D000284:Administration, Oral; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002400:Cathartics / Q000008:administration & dosage / Q000009:adverse effects*; D003113:Colonoscopy; D003404:Creatinine / Q000097:blood; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007668:Kidney / Q000187:drug effects; D007674:Kidney Diseases; D008297:Male; D010710:Phosphates / Q000008:administration & dosage / Q000009:adverse effects*; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000009:adverse effects*; D051437:Renal Insufficiency / Q000139:chemically induced*; D012307:Risk Factors
D015415:Biomarkers; D002400:Cathartics; D010710:Phosphates; D011092:Polyethylene Glycols; D003404:Creatinine; C018279:sodium phosphate